The overarching goal of my program of research is to improve the care of trauma patients. Trauma disproportionately affects the young and healthy, consuming over $US400 billion annually in direct medical costs and lost productivity. Regionalization, the transfer of moderately to severely injured patients to high level, academic trauma centers, improves outcomes. The American College of Surgeons - Committee on Trauma (ACS-COT) has attempted to improve regionalization by targeting known determinants of behavior: knowledge, attitudes, and organizational constraints. However, physician adherence to the ACS-COT's guidelines for the triage of trauma patients remains less than 60%. Current behavioral science literature suggests that other important determinants of decision making exist, including intuitive judgments (heuristics). The influence of heuristics on trauma triage decision making is unknown. An analysis of physician decision making in trauma triage that uses the insights and methodology of basic behavioral and social sciences research may allow the identification of additional determinants of non-adherence. By providing an explanation for the discrepancy that exists between the ACS-COT's efforts to change physician behavior and current practice patterns, this project holds the potential to alter the current paradigm of quality improvement in trauma. To achieve the goals of this research plan and to establish myself as a leading researcher in health services research related to trauma, I require further training in the following areas: 1) the theoretical constructs underlying physician decisio making; 2) the methodological tools necessary to conduct rigorous, sophisticated research in physician decision making, and 3) the management and leadership skills necessary to transition into an independent investigator. Under the guidance of my mentors, I have devised the didactic and research plan described in the following pages. Together, they will provide the necessary knowledge and skills to conduct cutting-edge, multi-disciplinary research that translates insights from behavioral science into an applied strategy to modify physician adherence to national trauma triage guidelines. The proposed research involves three inter-related studies. Aim 1 will refine a tool, developed in preliminary work, to study physician triage decisions under experimental conditions. Aim 2 will differentiate between the influence of faulty heuristics and knowledge deficits on physician triage decisions. Aim 3 will develop a novel intervention that targets either heuristics or knowledge deficits to help physicians make better triage decisions. These experiments set the stage for future work to test the effectiveness of the intervention in an R01-funded multi-center observational trial. I believe this investment in my career development will contribute to a new understanding of physician decision making in trauma, may improve the care provided to trauma patients, and has the potential to catalyze a change in our approach to quality improvement in health care.